Motor-driven pump



Jan. 26, 1954 w. RIMANN 2,667,127

MOTOR-DRIVEN PUMP Filed July 17, 1947 4 Sheets-Sheet l 0v l EN r03.- WAL r5 Ff/MANN av ATTORN V.

Jan. 26, 1954 Filed July 17, 1947 W. RIMANN MOTOR-DRIVEN PUMP .4 Sheets-Sheet 3 7b (VA/W861? 27 44 0/05 28 INVENTOR #4475? f/MA/v/v.

ATTORN EY Jan. 26J1Q54 w. RIMANN 2,667,127

MOTOR-DRIVEN PUMP Filed July 17, 1947 4 Sheets-Sheet 4 I N V EN TOR. n ALTEE EMA/WV.

BY fd/lm L ATTOR/VEK Patented Jan. 26, 1954 MOTOR-DRIVEN PUMP Walter Rimann, Winterthur, Switzerland, assignor to Sulzer Freres, Societe Anonyme, Winterthur, Switzerland Application July 17, 1947, Serial N0. 761,671

Claims priority, application Switzerland July 20, 1946 8 Claims.

pump and its driving motor are individually enclosed in chambers in which the same pressure 'prevails as in the high pressure circuit, and in which the motor chamber and the pump chamber are interconnected by a third chamber through which extends the shaft interconnecting the motor and the pump and in which the same pressure prevails as in the other two chambers.

A further object of the invention is the provision of a pump unit having a motor enclosed in a casing in which the same pressure prevails as in the high pressure pump circuit and in which said motor chamber and the interior of the high pressure pump circuit are separated by an elastic member.

An object of the invention is the provision of a high pressure, high temperature pump unit in which the pump and its driving motor are enclosed in chambers in which substantially the same pressure prevails, and in which both chambers are separated by a third chamber accommodating the shaft interconnecting the motor and the pump and being substantially under the same pressure as that in the other two chambers and in which said third chamber is cooled, to protect the motor against excessively high temperature.

An object of the present invention is the provision of a pump unit as set forth in the paragraph next above in which the chamber for the pump motor is cooled by the same fluid which cools the chamber between the motor chamber and the pump chamber.

An object of the present invention is the provision of a pump system as set forth above in which the motor is below the pump and the shaft is positioned substantially vertically and in which the pump has intake means positioned substantially above the center of the rotor of the pump and connected with the suction conduit, whereby said suction conduit supports the whole unit.

The pump unit according to the invention is particularly useful in steam generators with artificial or forced circulation where it is employed for circulating the hot boiler water. It is applicable to any process where-a hot liquid must be circulated. It may also be used to advantage for circulating a hydrocarbon together with catalyser in hydrogenation processes. When used for pumping a fluid which is sensitive to heat, the arrangement according to the invention serves for withholding the heat generated by the electric motor from said fluid.

Further and other objects of the present invention will be hereinafter set forth in the accompanying specification and claims and shown in the drawings which, by way of illustration, show what I now consider to be preferred embodiments of my invention.

In the drawings:

Fig. 1 is a side view of a pump unit including its mounting, support, and the connections to the pumping circuit, according to the invention;

Fig. 2 is a longitudinal section through a pump unit according to the invention;

Fig. 3 shows a section of a modification of a detail of the pump unit illustrated in Fig. 2;

Fig. 4 shows a section of another modification of a detail of the pump unit illustrated in Fig. 2;

Fig. 5 shows a section of a modification of another detail of the unit illustrated in Fig. 2;

Fig. 6 is a longitudinal sectional view of a modified center portion of a pump unit according to the invention;

Fig. 7 is a longitudinal part sectional view of the center portion and adjacent motor portion of a pump unit according to the invention having a modified cooling system;

Fig. 8 is a part sectional view of a modification of the detail shown in Fig. 4.

Like parts are designated by like numerals in all figures of the drawings.

Referring more particularly to Fig. 1 of the drawings, numeral i designates the suction conduit which is surrounded by an insulation 2 and to which a shut-off valve 3 is connected. Valve 3 is connected to flange 4 of an inlet socket portion of a pump casing 5. To the outlet socket portion 9 of the pump casing a shut-off valve I0 is connected which leads to discharge conduit H carrying an insulation 2'. Conduits I and H are connected with and support exclusively the whole casing with the pump unit therein and no other supports are needed.

Referring to Fig. 2, the pump rotor 15 is mounted to the upper end of shaft 16. The high pressure chamber 28 of the pump is closed by a wall 3i to the outer side of which an intermediary casing 6 is connected which supports in its interior a bearing H for shaft l6. Casing 6 extends below said bearing and forms a chamber surrounding the shaft and having a lower wall 1 having openings 23 and carrying a bearing [8 provided with a packing 29. A centrifuging ring 30 is connected with shaft [6 adjacent to packing 29 for reducing leakage through bearing [3. To the outside of wall 1 a casing 8 is connected which houses the pump motor having a rotor 20 and a stator 2|.

At the lower side of wall I a diaphragm or membrane 22 is provided separating chamber 21 formed by casing 6 and chamber 26 formed by casing 8 and equalizing the pressures in said chambers. Membrane 22 is corrugated and of annular configuration. Its outer rim is connected to the outer portion of flange or wall member 1 and its inner rim is connected with bearing l8.

Motor chamber 26 is filled with a pressure medium, such as water, oil or any other suitable fluid. Intermediary chamber 21 as well as pump chamber 28 are filled with the fluid pumped by the pump. Since the fluid pressure in the pump rotor chamber is transferred through leakage to the intermediary chamber and thrOugh a diaphragm to the motor chamber, the fluid pressure is the same in the entire casing.

The intermediary chamber 2? is cooled by means of a cooling coil 24 having an inlet l2 and an outlet [3. Casing 8 is provided with a jacket 24a the lower portion of which is connected for coolant flow with the outlet 93 by a conduit Hi. The jacket has an outlet 25.

Motor 20, 2t is protected against excessive heat by the cooled intermediary chamber 21 whereby heat coming from the hot pump casing 5 through wall 3! is removed by the coolant circulating in coil 24. In the illustrated embodiment of the invention, coolant is also circulated through jacket 24a of the motor casing. In this way the motor is not only protected against excessive heat but also against undesired temperature variations. The latter fact reduces variations of the volume of the fluids in chambers 25 and 27 which must be equalized by the membrane 22.

As long as the pressure in the pump circuit is low, the volume of the fluid in chamber 26 is relatively greater than when the pump circuit pressure amounts to, for example, 400 to 1600 lbs. per square inch and more. When the pressure in the pump circuit rises, the membrane 22 is bent down until there is substantially the same pressure on both sides of the membrane. In this case there is no flow of pressure fluid through bearing l 8. Membrane 22 is bent little when the free space in chamber 26 is small.

Instead of providing a cooling coil 2c in chamber 21, the coolant may be introduced directly into the chamber through inlet 12 and removed through outlet I3 and the coil be omitted. This is illustrated in Fig. 6.

In the embodiment of the invention shown in Fig. 2, the coolant cools chambers 26 and 2'! consecutively. Both chambers may be arranged in parallel with respect to coolant flow in which case the stream of coolant would be divided into two individual streams, one entering jacket 21a and leaving it at 25, and the other entering chamber 21 through inlet I2 and leaving it through outlet l 3. This is shown in Fig. '7.

The position of the yielding portion of the wall of chamber 26 may be different from that shown in Fig. 2. As illustrated in Fig. 3 flange 1 may be solid, without openings, and merely form bearing [8, and an annularly corrugated membrane 22' be disposed below bearing [9 and close the motor chamber completely thereat. In this case the chamber 32 below membrane 22 would have to be connected by a pressure equalizing conduit 33 with chamber 2'! and/or chamber 28.

Instead of providing an annular membrane on flange member 1 and openings in the latter, one opening only may be provided in said flange and a bellows member 34 closed at one end, be connected at its other end with flange '1" adjacent its opening, as shown in Fig. 4. The bellows member may extend into chamber 21, as shown in Fig. 4, or into chamber 26 as shown in Fig. 8 which ever is more convenient.

Chamber 2'! may be separated from pump chamber 28 by an annularly corrugated diaphragm or membrane 35 which could be connected with bearing I! and casing 6 as shown in Fig. 5. This arrangement is desirable in cases where the pump pumps or circulates an aggressive me dium.

While I believe the above described embodiments of my invention to be preferredembodiments, I wish it to be understood that I do not desire to be limited to the exact details of design and construction shown and described, for obvious modifications will occur to a person skilled in the art.

I claim:

1. A pump unit comprising a pump having a rotor and a casing, a motor having a shaft and a casing filled with a fluid, casing means interposed between said two casings and having an interior communicating with the interior of said first casing, said shaft extending from said motor casing through said casing means into said first casing and being connected with said rotor, said casing means and said motor casing having a common wall portion made of a yielding material.

2. A pump system for hot fluids, comprising a suction conduit and a pressure conduit, a pump unit including a motor having a shaft, a pump rotor connected to said shaft and spaced from said motor, casing means encasing said motor and said rotor and having a portion surrounding the space between said motor and said rotor, and cooling means disposed Within said portion, the part of the casing means encasing said rotor having an inlet socket portion connected with said suction conduit and an outlet socket portion connected with said pressure conduit for the sole support of said unit.

3. A pump unit for hot fluids, comprising a motor, a pump rotor disposed coaxially with and spaced from said motor, a shaft connecting said motor and said rotor, a bearing for said shaft disposed between said motor and rotor, a casing encasing said motor, said rotor, and space therebetween, cooling means disposed within said casing and between said motor and said rotor, and an annular, annularly corrugated diaphragm connected on its inside with said bearing and on its outside with said casing.

4. A pump unit as set forth in claim 3, said casing being divided substantially in the plane of said diaphragm and having flanges thereat, and support means for said bearing extending and held between said flanges.

5. A pump unit for hot fluids, comprising a motor having a shaft, a pump rotor connected to said shaft and spaced from said motor, casing means having a part encasing said motor and having a part encasing said rotor and having a portion surrounding the space between said motor and said rotor, a coolant circulating coil disposed within said portion, and a cooling jacket connected with the part of said casing means encasing said motor and being connected for coolant flow with said coil.

6. A pump unit comprising a pump having a rotor, a motor spaced from said rotor and having a shaft connected with said rotor, casing means surrounding said rotor, said motor, and said shaft, individual bearing means spaced apart and mounting said motor shaft and being disposed adjacent to said rotor and said motor, respectively, and facing one another, and partition means comprising a yielding member connected with each of said bearing means and with said casing and dividing said casing into three pressure fluid chambers, one chamber containing the rotor, another chamber containing the motor, and the third chamber being between the first two chambers.

7. A pump system comprising an inlet and an outlet conduit for a hot, high pressure fluid, a casing, a pump having a rotor rotatably sup ported in said casing, a motor rotatably supported in said casing and being spaced from said rotor, a shaft interconnecting said motor and said rotor, said casing having a part forming a chamber for said rotor, a part forming a chamher for said motor, and a part forming a chamber interposed between said first two parts, cooling means in said last mentioned chamber, a. pressure fluid filling each of said chambers, and fluid pressure transfer means interposed between said chambers and affording substantially the same fluid pressure in the entire casing as in the rotor chamber, said casing being con nected with and exclusively supported by said inlet and outlet conduits.

8. A pump system comprising an inlet and an outlet conduit for a hot, high pressure fluid, a casing, a pump having a, rotor rotatably supfluid pressure transfer means interposed between said chambers and affording substantially the same fluid pressure in the entire casing as in the rotor chamber, and a coolant circulating coil connected to a coolant supply and disposed in said chamber interposed between the parts forming the chambers for said rotor and said motor.

WALTER RIMANN.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,198,558 Lawaczeck Sept. 19, 1916 1,736,002 Frickey et al Nov. 19, 1929 2,075,395 Harmon Apr. 6, 1937 2,266,039 Hollander et al Dec. 16, 1941 2,293,616 Myers Aug. 18, 1942 2,301,063 McConaghy Nov. 3, 1942 2,312,526 Curtis 1 Mar. 2, 1943 2,404,783 Blom July 30, 1946 2,423,436 Blonr July 8, 1947 2,423,825 Blorn July 15, 1947 2,472,010 Gilman May- 31, 1949 FOREIGN PATENTS Number Country Date 17,716 Great Britain Aug. 3, 1911 209,606 Great Britain Jan. 17, 1924 

